Pipe Fitting by Types

Pipe fittings are widely demanded for any piping and plumbing systems
used in industrial and commercial applications. Fittings allow pipes to
be joined or installed in the appropriate place and terminated or closed
where necessary. Fittings are available in various shapes and sizes.
They can be expensive, require time, and different materials and tools
to install. They are an essential part of piping and plumbing systems.
There are thousands of specialized fittings manufactured. Each type of
pipe or tube requires its own type of fitting, but usually all pipe
fittings share some common features. Pipe fittings are available
everywhere where plumbing materials are sold.

How are pipe fittings connected to pipes?
Pipe fittings are either male fittings or female fittings. In threaded
pipe fittings, female threads are on the inside while male threads are
on the outside. Pipe fittings that have one female end and one male end
are called street fittings. Pipe fittings are used to connect pipes or
tubes in two ways:

By threading: Threaded pipes screw together to connect or
join. Generally metal pipes are threaded and they have threaded
fittings.

By slip fit: Slip fit pipes use sleeves that slip into
one another. The plastic pipes are either threaded or slip fit.

Accordingly pipe fittings are organized as follows:

Male threaded: Exterior threads. Are screwed into the
inside of pipe end of a larger diameter with internal threading.

Female slip fit: Female slip fit: There are no threads.
Made to slip into slightly larger male sleeve.

Purpose of a pipe fitting:
The basic purposes of any pipe fitting are as follows:

Connecting the bores of two or more pipes or tubes.

Connecting pipe sections.

Connecting a pipe to a different apparatus.

Changing the direction of fluid/liquid flow.

Maintaining or regulating the flow.

Closing and sealing a pipe.

Selection criteria for pipe fittings:
Pipe fittings are to be chosen considering certain factors. They are as
follows:

Connection types: When purchasing pipe fittings, you
should be aware of the fact that a fitting can have two different
connector types. One end of the fitting might be female threaded
while the other female threaded. One end might be male slip while
the other end is threaded, in the case of plastic fittings. They can
also have matching ends which can accommodate any requirement.

Materials of construction: As a rule, the pipe fitting
should be of the same material as the material used in the making of
the pipe in which it is to be fitted. However, in some cases,
materials conforming to certain codes or standards can also be used
in pipes of another material.

Check for flow: To keep the flow consistent, the ends of
pipe fittings should be slightly larger than the rest of the pipe so
that they can accommodate connections without narrowing the inner
diameter (ID) of the pipe.

Type of fitting: Besides pipe materials, pipe fittings
are identified by the type of fitting — threaded or slip, male
or female.

Size: When measuring the size of pipe fittings, it is to
be noted that the male threaded fittings are measured to the outside
edge or OD, while female fittings are measured to the inside edge of
the inlet or ID.

Thickness: Just as pipes are available in a number of
different thicknesses or "schedules", so also the pipe
fittings.

Design: Each pipe or tube is designed to carry certain
specific types of fluids, liquids, gases, chemicals under varying
conditions. Accordingly, the pipe fittings are also available in
variety of designs.

Standards and codes: There are certain standards and
codes set by various organizations by which the different pipe
fittings are graded. For example, ASTM, ASME, BSP etc. are certain
standards assigned to pipe fittings and those standards dictate
their use.

Types of pipe fittings:
Depending on the purposes served, pipe fittings can be categorized as
under: